In order to provide or create a flat surface, it is sometimes necessary to perform a cutting operation. In the case of a shell and sun gear assembly, this may involve a thrust face surface cut that cuts across materials having different properties. For example, the sun gear and the shell may be made of different material compositions and/or their materials may have different hardnesses. In addition, a weld between the gear and the shell may add another different material composition and/or hardness value. The cut, which may be referred to as a thrust face machining operation, may be performed by a turning operation wherein the assembly is rotated and cut by a non-rotating tool.